1. Heating potassium permanganate to produce oxygen, the safe operation after the end of the experiment is first (), and then () 2. The function of ice water in water tank is () 3. It is proved that in the reverse catalysis test of hydrogen peroxide, 1.（ ） 2. Put manganese dioxide into large test tube and add 5ml hydrogen peroxide 3. After the reaction, filter, wash, dry and weigh the solid substance in the large test tube 4.（ ） After finishing this experiment, we need to prove the catalytic effect of manganese dioxide, and add an inquiry experiment: Inquiry () 4. The factors that affect the rate of chemical reaction may be ()

1. Heating potassium permanganate to produce oxygen, the safe operation after the end of the experiment is first (), and then () 2. The function of ice water in water tank is () 3. It is proved that in the reverse catalysis test of hydrogen peroxide, 1.（ ） 2. Put manganese dioxide into large test tube and add 5ml hydrogen peroxide 3. After the reaction, filter, wash, dry and weigh the solid substance in the large test tube 4.（ ） After finishing this experiment, we need to prove the catalytic effect of manganese dioxide, and add an inquiry experiment: Inquiry () 4. The factors that affect the rate of chemical reaction may be ()

1 turn off the alcohol lamp and take out the tube from the water
2 control the reaction rate
1 check the test device
4. Arrange test equipment
Influence of purity of manganese dioxide on experiment
4 temperature, manganese dioxide purity, hydrogen peroxide concentration

Chemistry experiment in grade three of junior high school
Answer quickly

The color of common chemical substances in junior high school (1), color of solid 1, red solid: copper, iron oxide 2, green solid: basic copper carbonate 3, Blue Solid: copper hydroxide, copper sulfate crystal 4, purple black solid: potassium permanganate 5, light yellow solid: sulfur 6, colorless

The teacher didn't make it clear, as follows
Dictation experiment operation 3-6, should write, the negative scoring criteria: to report
(every page of our book is an experiment. On the positive side are the test questions, and on the negative side are the scoring standards (that is to say, if something is wrong, you have to deduct points))

It's the process of the experiment

50 g of 10% NaCl solution was prepared
2. Determine the pH of unknown solution with pH test paper
The activity order of Fe, Cu and Al is proved by experiments
Neutralize the sodium hydroxide solution with hydrochloric acid
5. Explore the endothermic or exothermic phenomenon of material dissolution
6 explore the solubility of NaCl in a certain amount of water
Identification of NaCl and calcium carbonate by hydrochloric acid
8. Assemble a simple device for collecting carbon dioxide in the laboratory
9 assemble the oxygen collection device in the laboratory
10. Weigh 12.5g NaCl with tray balance

The combustion of magnesium in air: 2mg + O2 ignites 2MgO 2, iron in oxygen: 3Fe + 2O2 ignites fe3o43, aluminum in air: 4Al + 3O2 ignites 2al2o34, hydrogen in air: 2h2 + O2 ignites 2h2o5, red phosphorus in air: 4P + 5o2